Common problems of hot reflux extraction and concentration unit

When operating an evaporator or extraction tank, several issues may arise, and here are the causes and solutions:

1. **Evaporator Vacuum Too High (Low Evaporation Temperature):**

- **Cause:** The heating steam valve is too closed, and the cooling water valve is too open.

- **Solution:** Open the steam valve, close the cooling water valve, and use a circulating water pump to raise the temperature by closing the tank inlet valve.

2. **Evaporator Vacuum Too Low (High Evaporation Temperature):**

- **Cause:** The heating steam valve is too open, and the cooling water valve is too closed.

- **Solution:** Close the heating steam valve and open the cooling water valve.

3. **Concentration Tank Liquid Level Too High:**

- **Cause:** Excessive liquid intake.

- **Solution:** Reduce the fluid volume and close the water inlet valve if necessary. Return the liquid to the evaporator through the endoscope center before re-entering via the liquid valve.

4. **Drop in Condensing Reflux Extraction Tank Temperature:**

- **Cause:** Insufficient concentrated steam.

- **Solution:** Increase the heating steam valve opening to enhance evaporation and close the cooling valve.

5. **Drop in Extraction Tank Condenser Reflux Temperature:**

- **Cause:** Over-concentration due to excessive heating and evaporation.

- **Solution:** Open the cooling valve and close the heating steam valve to reduce evaporation.

6. **Rising Concentrated Foam Layer in the Extraction Tank:**

- **Cause:** Excessive liquid entering the vacuum, leading to foam formation.

- **Solution:** Lower the liquid level, reduce the vacuum (e.g., by adding a small amount of oil to decrease surface tension and eliminate foam), and avoid high vacuum levels, as they increase evaporation and bubble formation, causing liquid losses.

By addressing these issues with the appropriate troubleshooting steps, the evaporator and extraction tank can operate efficiently and maintain optimal performance.